[Wtd] Someone helpful who can build a DCB1 preamp for me

[rescuest3ve]

Hi all,

Apologies if this is in the wrong thread, but I'd like to employ someone's expertise to build me a hot-rodded Nelson Pass B1 DIY pre, just like this one described here:

https://theartofsound.net/forum/archive/index.php/t-61045.html

Jez Arkless is swamped for a while, so he's a no-go, but is there anyone else about that would be willing to give it a bash for me? I'd try myself, but I'll only end up burning down the living room.

Cheers
Steve

 

[Dan K]

Honestly don't bother. Research Broskie CCDA, or Aikido.

 

[Dan K]

Actually just buy Ant's Croft RS from the classifieds

 

[martin clark]

Hardly helpful - the OP desires a Nelson Pass design built.

 

[sq225917]

Do you have the parts?

 

[Dan K]

Yes, yes. I know, but it's not a great pre. I'm trying to be helpful.

There's a tonal hardness to the B1 that you can never get rid of. YMMV. Etc etc. Do whatever you want. Waste your time OP. Pay for someone else to build a B1 and be happy.

 

[Marra]

So what you are after is the Salas DCB1 hotrod version not the actual B1?

 

[sq225917]

Or the topping pre90 if you don't need gain. Utterly transparent.

 

[eastone]

Alan Firebottle has built these in the past if I’m not mistaken?

 

[glenn jarrett]

If your after one of these then i can help
i have also found a replacement for the 2sk170bl for this application and it works fine
20200213_155723 by glenn jarrett, on Flickr
20210106_100454_001 by glenn jarrett, on Flickr

 

[glenn jarrett]

also have a spare board but its a ebay one not from diy audio but the same tracks and a bit more space
20210219_104915 by glenn jarrett, on Flickr
20210219_104922 by glenn jarrett, on Flickr

 

[chiily]

If your after one of these then i can help
i have also found a replacement for the 2sk170bl for this application and it works fine
20200213_155723 by glenn jarrett, on Flickr
20210106_100454_001 by glenn jarrett, on Flickr

Green,

That is such a neat build. Where did you get the heatsinks from please?

 

[glenn jarrett]

Hi Chiily
SK 81/ 50 SA Fischer Elektronik, Heat Sink, Extruded, 3.4 K/W | Farnell
i used thermal conductive glue and glued the sinks to a 4mm ally plate
20200213_155735 by glenn jarrett, on Flickr

 

[chiily]

Hi Chiily
SK 81/ 50 SA Fischer Elektronik, Heat Sink, Extruded, 3.4 K/W | Farnell
i used thermal conductive glue and glued the sinks to a 4mm ally plate
20200213_155735 by glenn jarrett, on Flickr

Thanks Glenn.

 

[Mr Ian]

Few people on aos have built these, and at least couple offer build services

 

[fran]

i have also found a replacement for the 2sk170bl for this application and it works fine

Don't hold back - tell us more!!

 

[sq225917]

Lsk170, or bf862 with 100 ohm Gate stopper?

 

[glenn jarrett]

no i used the 2sk209gr which has an idss of around 3-4 ma so the 6 un matched are ok single and the 4 matched i doubled them up and managed to get 2 matched quads from 75 fets
you will need a sot23 test adaptor and a lot of time !
i have 6 unmatched and a matched quad @ 9ma if you want them £25 posted
20201128_133255 by glenn jarrett, on Flickr
20201128_133243 by glenn jarrett, on Flickr
20201127_222729 by glenn jarrett, on Flickr
20210103_151909 by glenn jarrett, on Flickr
20201220_172338 by glenn jarrett, on Flickr

 

[glenn jarrett]

sot23 test adaptor
dca by glenn jarrett, on Flickr

 

[sq225917]

I applaud your efforts. Proper matching is a herculean task.